Raster · collection · 2010
Africa Soil Information Service (AfSIS): Topographic Wetness Index (TWI)
Listed in NASA Earthdata CMR
The Africa Soil Information Service (AfSIS): Topographic Wetness Index (TWI) is a 90m raster dataset showing zones of increased soil moisture where the landscape area contributing runoff is large and slopes are low.
Description
The topographic wetness index, originally developed by Beven and Kirkby in 1979, provides a measure of wetness conditions at the catchment scale. This dataset combines local upslope contributing area and slope using the digital elevation model AfHydSRTM, which is based on the CGIAR-SRTM 90m Version 4.
The dataset was produced at the World Agroforestry Centre (ICRAF) in Nairobi, Kenya and is distributed by the Africa Soil Information Service. This index is commonly used in soil landscape modeling and in the analysis of vegetation patterns. The images and data are available from the Africa Soil Information Service (AfSIS) in Geographic Tagged Image File Format (GeoTIFF) format via download at africasoils.net/.
Links
Get the data
- Data in GeoTIFF format ciesin.columbia.edu/repository/afsis/data/srtm_twi/AfSIS_TWI_nw.tar.gz ↗
download · from NASA CMR
- africasoils.net /services/data ↗
Data in GeoTIFF format. Image accessible in pre-set files corresponding to a specific country in Africa or a user-defined area of the continent
download · from NASA CMR
- Data in GeoTIFF format ciesin.columbia.edu/repository/afsis/data/srtm_twi/AfSIS_TWI_sw.tar.gz ↗
download · from NASA CMR
- Data in GeoTIFF format ciesin.columbia.edu/repository/afsis/data/srtm_twi/AfSIS_TWI_se.tar.gz ↗
download · from NASA CMR
- Data in GeoTIFF format ciesin.columbia.edu/repository/afsis/data/srtm_twi/AfSIS_TWI_ne.tar.gz ↗
download · from NASA CMR
Catalogue records · 2
- CMR record cmr.earthdata.nasa.gov/search/concepts/C1214155403-SCIOPS.html ↗
catalogue entry · from NASA CMR
- CMR UMM-JSON cmr.earthdata.nasa.gov/search/concepts/C1214155403-SCIOPS.umm_json ↗
metadata API · from NASA CMR
Topics
- Stated by source
- Contour Maps · Not provided · Soil Absorption · Soil Erosion · Soil Moisture/Water Content · Terrain Elevation · Topographical Relief Maps
- Inferred from text
- Image 75%
Provenance · 1 source records, 16 field assertions
| Source | Key | Last seen | Raw |
|---|---|---|---|
| NASA Earthdata CMR | C1214155403-SCIOPS | 10 d ago | JSON v1 |
| Field | Assertion | Extractor | Evidence |
|---|---|---|---|
| access_level | source · NASA CMR | connector:nasa_cmr@1.0.0 | |
| concepts[measured_variable].gcmd:earth-science/land-surface/soils/soil-absorption | source · NASA CMR | connector:nasa_cmr@1.0.0 | |
| concepts[measured_variable].gcmd:earth-science/land-surface/soils/soil-erosion | source · NASA CMR | connector:nasa_cmr@1.0.0 | |
| concepts[measured_variable].gcmd:earth-science/land-surface/soils/soil-moisture-water-content | source · NASA CMR | connector:nasa_cmr@1.0.0 | |
| concepts[measured_variable].gcmd:earth-science/land-surface/topography/terrain-elevation | source · NASA CMR | connector:nasa_cmr@1.0.0 | |
| concepts[measured_variable].gcmd:earth-science/land-surface/topography/terrain-elevation/contour-maps | source · NASA CMR | connector:nasa_cmr@1.0.0 | |
| concepts[measured_variable].gcmd:earth-science/land-surface/topography/terrain-elevation/topographical-relief-maps | source · NASA CMR | connector:nasa_cmr@1.0.0 | |
| concepts[modality].local:modality:image | enrichment · NASA CMR | keyword-concept-rules@1.0.0 | title+description (75%) |
| concepts[platform].gcmd_platform:not-provided | source · NASA CMR | connector:nasa_cmr@1.0.0 | |
| description | source · NASA CMR | connector:nasa_cmr@1.0.0 | /umm/Abstract |
| license_text | source · NASA CMR | connector:nasa_cmr@1.0.0 | |
| publication_date | source · NASA CMR | connector:nasa_cmr@1.0.0 | |
| spatial | source · NASA CMR | connector:nasa_cmr@1.0.0 | /umm/SpatialExtent |
| temporal | source · NASA CMR | connector:nasa_cmr@1.0.0 | /umm/TemporalExtents |
| title | source · NASA CMR | connector:nasa_cmr@1.0.0 | /umm/EntryTitle |
| version_label | source · NASA CMR | connector:nasa_cmr@1.0.0 |